Astrobiologists, also known as exobiologists, life scientists, and space scientists, study the origin of all life forms—from a simple one-celled organism, to plants, to human beings. They study and research the evolution, distribution, and future of these life forms, on earth as well as on other planets in our solar system and beyond. Many astrobiologists are employed by the National Aeronautics and Space Administration (NASA) and other government-funded agencies. They are also employed at private research institutions and colleges and universities.